Safety-chuck.



J. H. RICHARDSON.

SAFETY CHUCK.

APPLICATION FILED AUG. 5.1915.

gamma Jan. 9,1917.

x 16 0 lgwsf V fnvemior: Jwsefifiicizdrdyon JESSE H. RICHARDSON, OF PHILADELPHIA, PENNSYLVANIA.

SAFETY-CHUCK.

Specification of Letters latent.

Patented J an. 9, 191?.

Application filed August 1915. Serial No. 43,737.

To all whom it may concern:

Be itknown that I, Jnssn H. RICHARDSON, a citizen of the United States, residing in the city of Philadelphia, county of Philadelphia, 5 and State of Pennsylvanla, have invented certain Improvements in Safety-Chucks, of which the following is a specification.

My invention relates to a safety chuck designed more particularly for operating drills 35 and reamers, and its primary object is to provide an improved device for-protecting operators of drill presses and reaming gauntrees.

The improvements are characterized by simple, certain and eflicient locking and unlocking means adapted to be automaticall engaged by the engagement of the tool with the work and automatically disengaged when the tool feed is off or the tool is not subject to the resistance of the work, so that the chuck, together with the tool, will be stopped upon encountering slight resistance, an engagement with .an operators clothing stopping these parts and protecting him from the injuries that frequently occur to operators as a result of their sleeves being wound up when caught.

The improvements effect the further desideratum of preventing the disengagement of the chuck and the tool running ahead of the feed when the helical cutting edge makes a working engagement that tends to draw the tool forward.

The characteristic advantages of the in- 85 vention will more fully appear from the following description and the accompanying drawings of a preferred form thereof.

In the drawings, Figure 1 is a part sectional elevation of mechanism embodying my improvements; Fig. 2 is an enlarged sectional view of details of the construction shown in Fi 1; Fig. 3 is a further sectional view of the etails of Fig. 2 shown in different relation; Fig. 4 is an enlarged bottom plan view of the base of the driving shank shown in Fig. 1; and Fig. 5 is an enlarged sectional view taken on the line 5'5 of Fig. 1.

The mechanism illustrated comprises the driving shank 1 (adapted to be engaged in a drill ress or reaming gauntree) having the circuliir base 2, provided with the male thread 3, the jaws 4 containing the springs 5, and the axial socket 6 wit relation to which the jaws are symmetrically disposed.

A cylindrical sleeve 6" is provided with the female thread 7 within its top which is adapted to engage the thread 3, whereby the shank 1 carries the sleeve, the sleeve containing the circular interior race 8 intermediate its length for the antifriction balls 9 and having fixed on the lower end thereof the collar lO containin the circular race 11 for the antifriction bal s 12.

The cylindrical chuck head 13, having jaws 14 complementary to the jaws 4, is disposed in the sleeve 6' where it is revoluble in contact with the balls 8, which guide it by contact with the eriphery of its cylindrical body, and the balls 12 which support it through their engagement with the plane surface 15. A cylindrical stem 16 on the top of the head 13 enters the socket 6 in freely movable relation and a cylindrical stem or neck 17 on the lower end of the body extends through the collar 10, the neck 17 containing a threaded axial socket 18 therein. A bearing ring 19 of soft metal surrounds the neck 17 within the collar 10 to which it is fixed, the top of the ring serving as a retainer for the balls 12.

The chuck 20 has on the neck or stem 21 at its top a threaded stud 22' which is engaged in the socket 18, whereby the chuck and the bit or tool 23' engaged therein are revoluble by the head.

The shank 1 is revoluble independently of the connected head 13, chuck 20 and tool 23 excepting when, by an upward thrust on the tool or its engagement b the work, the forwardly feeding shank e ects the engagement of its jaws 4 with the jaws 14, by the entry of the tooth 4 of square cross section into the notch 14 of like cross section and the entry of the tooth 14 of square cross section into the notch 4 of like cross section against the actions of the coiled springs 5, which extbnd transversely to the axis of revolution 9. d normall into the notches 4". This eng gement w1ll be maintained as the shank is ed forward with the tool in engagement with the work, even insuch cases as when the helical fluting of the tool is engaged by a projection of the work which tends to feed the tool forward faster than the feed of the machine, for the square engagement between the jaws maintains the locked relation so long as thereis resistance to the rotary movement of the tool. But when the resistance to the rotary movement of the tool has nally or drop the arts 13, 20 and 23 with a been eliminated, as where the drill or reamer has passed through the work, the springs 5 expand and press againstthe jaws 14 which are thereby disengaged from the jaws 4 and the parts 13, 20 and 23 are moved longitudidown by gravity the distance permitted by the controlling devices 6, and 13, so that the jaws 14 clear the jaws 4, in which relation, whether before the toolengages the work or after it has passed through, slight'resistance to the spinning of will stop them. aving described my invention, I claim:

1. In an instrument of the character described, revoluble driving means provided with a locking device and a controlling device, in combination with revoluble driven means provided with a locking device adapted to be engaged by said locking device first named, means for turning said drivin means to effect the disengagement thereo from said locking device and a controlling device coacting with said controlling device first named, whereby said means second named are permitted a limited longitudinal movement relative to said means first named and said means first named are adapted to revolve independently of said means second named.

2. In an instrument of the character described, revoluble driving means provided locking device adapted for positive engagement and a controlling device, in combination with revoluble driven means provided with a locking device adapted to be engaged positively by said locking device first named and a controlling device coacting with said controlling device first named, anti-friction bearings whereby said means are journaled relatively, said means second named being permitted a limited longitudinal movement relative to saidmeans first named and said means first named being adapted -to revolve independently of said means second named, and a spring for disengaginlg said locking devices.

3. 11 an instrument ,of the character described, a shank having connected therewith a sleeve and a clutching device, in combination with a chuck provided with a head having a clutching device movable in said sleeve into engagement with said clutching device first named, said devices comprising means whereby when engaged said shank and chuck are by the revolution of said shank locked together against relative longitudinal movement.

4. In an instrument of the character described, a driving shank comprising one or morejaws and a sleeve having a cylindrical interior surface concentric with said shank, in combination with a chuck provided with a cylindrical head havin a limited longitudinal movement in said s eeve and one or more awsadapted for engaging said jaw or jaws first named, and means for automatically turning said head to effect the separation of the engaging jaws.

5. In an instrument of the character described, a revoluble shank provided with jaws having a bearing surface substantially at right angles to the axis of said shank and a sleeve having a cylindrical interior surface surrounding said jaws, said surfaces and jaws being concentric with said shank, in combination with a chuck provided with a cylindrical head having a limited longitudinal movement in said sleeve and jaws on said head having bearing surfaces disposed substantially at right angles to the axis of said shank and adapted for engaging said bearing surfaces first named.

6. In an instrument of the character described, a revoluble shank provided with jaws having a bearing surface substantially at right angles .to the axis of said shank, and

a sleeve having a cylindrical interior surface said surface and jaws scribed, a revoluble shank provided with a sleeve, a jaw fixed within said sleeve, a chuck provided with a head revoluble and longitudinall movable in said sleeve, a jaw ed to sai head and adapted to engage said jaw first named, and a spring for turnin said head to effect the disengagement of said j aws.

8. In an instrument of the character described, a revoluble shank having concentric jaws rovided with bearin disposed transverse y to the axis thereo with a revoluble device provided with concentric jaws having bearin surfaces disposed transversely to its axis and adapted for engaging said jaws first named in locking relation, means comprisin anti-friction bearings whereby said chuck is permitted a limited longitudinal movement relative to said shank and said shank is permitted to revolve independently of said device, and a spring for turning said device to effect the disengagement of said jaws.

9. In an instrument of the character described, a revoluble shank having concentric jaws and a sleeve having a concentric cylindrical interior surface, said sleeve provided with a collar thereon concentric with said surface, in combination with a chuck having ahead with a cylindrical surface dispose in said sleeve and 'aws on said head adapted for engaging sai jaws first named, antifriction balls disposed between said cylindriin combination cal surfaces, and anti-friction balls carried by said collar to provide bearings for said head, said head being movable longitudinaily and revolubly in said sleeve.

10. In an instrument of the character described, a shank provided with a tooth and a notch, a sleeve fixed to said shank, a chuck provided with a head adapted to revolve and reciprocate axially in said sleeve, said head provided with a tooth adapted to be "en- 10 gaged in said notch and a notch adapted to receive said first named tooth, and means whereby said teeth are automatically disen gaged from said notches.

JESSE H. RICHARDSON. 

